28691401 has 2 divisors, whose sum is σ = 28691402. Its totient is φ = 28691400.

The previous prime is 28691381. The next prime is 28691417. The reversal of 28691401 is 10419682.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28676025 + 15376 = 5355^2 + 124^2 .

It is a cyclic number.

It is not a de Polignac number, because 28691401 - 2¹³ = 28683209 is a prime.

It is not a weakly prime, because it can be changed into another prime (28631401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14345700 + 14345701.

It is an arithmetic number, because the mean of its divisors is an integer number (14345701).

Almost surely, 2^28691401 is an apocalyptic number.

It is an amenable number.

28691401 is a deficient number, since it is larger than the sum of its proper divisors (1).

28691401 is an equidigital number, since it uses as much as digits as its factorization.

28691401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 28691401 is about 5356.4354752018. The cubic root of 28691401 is about 306.1380078637.

It can be divided in two parts, 28691 and 401, that added together give a palindrome (29092).

The spelling of 28691401 in words is "twenty-eight million, six hundred ninety-one thousand, four hundred one".